Recent studies indicate that 4- aminosalicylic acid (4-ASA) is effective in inflammatory bowel disease. Therapeutic intralumial concentrations of this drug may be achieved by oral administration of 6 gm per day of uncoated 4-ASA. To test the theraputic efficacy and safety of 4-ASA in symptomatic small bowel Crohns disease, a 3 month, double-blind, placebo-controlled trial at four centers is proposed. The PI is at UVM and all protocols originated from UVM. Crohns disease will be defined by clinical, radiologic, endoscopic, surgical and histological criteria. Persons with infectious or ulcerative colitis, hepatic or renal disease, preganacy, or a Crohns disease activity index (CDAI)>450 will be excluded. Disease activity will be judged by the CDAI scoring system with a CDAI of >150 nessary for entry into the study. Patient recruitment is continuing at UVM and the other centers as well.